I usually just use the terrain tools to make small hills/irregularities to make different builds look more interesting.
The latest thing I tried was to make a tiny house on wheels by having the house actually "floating" a bit above ground. To do that, I made a two story house, lowered the first story down underground until the second story was just above ground level, and then deleted the first level. The ground levels out that way and gives the house a floating effect. Then I made some wheel CC and added that to the sides. Although, it is technically still on the second floor, and I'm not sure about playability that way, but I just made it for the building fun rather than playing. :)
